1. Field of the Invention
The present invention relates to a machine for working on a ballast bed supporting a track, which comprises a machine frame, undercarriages supporting the machine frame on the track, a ballast storage receptacle on the machine frame, and a suction arrangement on the machine frame, the suction arrangement comprising a suction unit and a suction conduit connected to the suction unit, the suction conduit terminating in a vertically and transversely adjustable suction snout defining a suction opening for aspirating ballast into the ballast storage receptacle.
2. Description of the Prior Art
One type of such a machine has been described in German utility model No. 8,236,650, published Jun. 30, 1983. This machine has a suction snout projecting from the machine frame and defining a suction opening for aspirating ballast from the track bed and a suction conduit for conveying the ballast to a ballast storage receptacle. After the aspirated ballast has been cleaned, the cleaned ballast is returned to the track bed by a transversely extending conveyor band.
Another type of such a machine is disclosed in German patent No. 2,136,306, wherein the suction snout projecting from the machine frame carries a suction nozzle with vibrators for loosening the ballast to be aspirated. An auxiliary port is arranged adjacent the suction opening and is connected to the input opening of a suction unit to enhance the aspirating capacity.
U.S. Pat. No. 4,938,239 discloses a mobile machine for cleaning the surface of a track bed by aspiration. A suction head extends over the entire width of the track bed and is connected to a suction unit. The suction head has a compressed air supply nozzle in the suction opening for causing turbulence in the surface dirt and this nozzle is connected to the output opening of the suction unit. Similar machines incorporating such a compressed air/suction system are disclosed in German patent No. 3,318,756 and Austrian patent No. 312,028.